Just the way I see it, in this MCU, I don't see Stark or the Illuminati shooting Hulk into space. Someone else would have to do it.

Either that, or Hulk/Banner would have to do something pretty egregious or something pretty terrible for Iron Man to decide to do that. Maybe Hulk is framed and the heroes COLLECTIVELY see this as the best solution. Maybe Banner himself agrees to it.

But the problem ultimately is that World War Hulk is a stupid story where the Hulk is the bad guy and is in the wrong and is beating up other heroes. Audiences aren't going to go for that now that they love Hulk and love seeing Hulk team up with other heroes.

How do you justify the Hulk returning to earth and basically preparing to murder all the other heroes because he's duped by his insect buddy?

Also not to mention, in this version its a more intelligent and talkative Hulk which thus far, Marvel has been reluctant to depict onscreen.